Isso é respondido no material de Galadriel e Celeborn em Contos Inacabados; Apêndice B, Os Príncipes Sindarin dos Elfos Silvestres :
Thranduil é, portanto, um dos, ou na pior das hipóteses descendentes, dos Sindar Elfos de Beleriand na Primeira Era, que nunca viram Valinor, mas que mesmo assim fizeram a Grande Jornada e chegaram a Beleriand antes do Nascer do Sol.In Appendix B to The Lord of the Rings, in the headnote to the Tale of Years of the Second Age, it is said that "before the building of the Barad-dûr many of the Sindar passed eastward, and some established realms in the forests far away, where their people were mostly Silvan Elves. Thranduil, long in the north of Greenwood the Great, was one of these."
Seu povo, por outro lado, é predominantemente Silvan Elfos ( não Sindar) que eram de pessoas diferentes e menores. A diferença específica também é definida na mesma fonte, desta vez Apêndice A, Os elfos silvestres e sua fala :
The Silvan Elves (Tawarwaith) were in origin Teleri, and so remoter kin of the Sindar, though even longer separated from them than the Teleri of Valinor. They were descended from those of the Teleri who, on the Great Journey, were daunted by the Misty Mountains and lingered in the Vale of Anduin, and so never reached Beleriand or the Sea.
Finalmente, o texto de O Hobbit resume tudo isso (mas note que ele remonta a um tempo anterior à concepção completa das relações entre os diferentes povos élficos):
They differed from the High Elves of the West, and were more dangerous and less wise. For most of them (together with their scattered relations in the hills and mountains) were descended from the ancient tribes that never went to Faerie in the West. There the Light-elves and the Deep-elves and the Sea-elves went and lived for ages, and grew fairer and wiser and more learned, and invented their magic and their cunning craft, in the making of beautiful and marvellous things, before some came back into the Wide World. In the Wide World the Wood-elves lingered in the twilight of our Sun and Moon but loved best the stars; and they wandered in the great forests that grew tall in lands that are now lost.
Então, sim, Thranduil é mais nobre que o seu povo, porque ele é descendente de um diferente e mais nobre povo élfico.